Presently, there are scroll compressors which use a pair of spiral involutes formed on a pair of plates. One plate is typically fixed, and the other plate travels in orbiting pattern in respect of the fixed plate, thereby gradually compressing a fluid. The fluid is eventually discharged through a discharge port. Known scroll compressors rely on various orbit control structures which enable the orbiting scroll to maintain a desired trajectory for efficient operation. The known orbit control structures include a ball coupling ring, an eccentric motion bearing, an Oldham coupling, a pin and barrel, and a pin and ring, for example.
One such control structure is disclosed in U.S. Pat. No. 5,147,192, hereby incorporated herein by reference in its entirety. The '192 patent describes a scroll compressor including an orbit scroll having a first forming plate affixed thereto and a fixed plate having a second forming plate affixed thereto. The forming plates face one another and include a plurality of circular recesses formed therein on each of the facing surfaces. The recesses are formed in an annular pattern. A coupling lug is disposed between each facing pair of recesses. The recesses can be formed in the fixed plate and the orbit scroll.
U.S. Pat. No. 5,456,584, hereby incorporated herein by reference in its entirety, discloses an anti-rotation mechanism for a scroll compressor. The mechanism includes a fixed ring attached to a race and a rear housing. A moveable ring is affixed to a pressure receiving wall of an orbit scroll. Both the fixed ring and the moveable ring include a plurality of circular holes formed therein. The holes are adapted to receive one of a plurality of cylindrical pins therein. Alternatively, the mechanism includes a plurality of pins, each having two ends protruding from a moveable ring. The pins cooperate with a plurality of holes formed in a moveable plate and a fixed pressure-receiving wall.
In U.S. Pat. No. 6,264,444, hereby incorporated herein by reference in its entirety, a scroll compressor is disclosed which includes an orbital rotating mechanism disposed at an end of an orbit scroll. The mechanism includes a plurality of guide holes formed in a front housing and a pressure receiving plate. The plate is disposed between the orbit scroll and the front housing. A plurality of pins is attached to the back surface of the orbit scroll. The pins are adapted to be received in the guide holes. An outer peripheral surface of each of the pins makes sliding contact with an inner peripheral surface of each of the guide holes.
Although the aforementioned structures operate effectively, the structures require numerous parts. Additionally, the structures are difficult to manufacture, costly, heavy, and lack durability.
It would be desirable to produce an orbit control device for a scroll compressor wherein a cost, complexity, and weight thereof are minimized and a durability thereof is maximized.